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How can I establish a reference level?

With now 350+ hours on my new rear end (I hope it is OK to call the new speakers that, given the common use of the expression front end for the source) I am trying to understand gain and how it relates to listening level. The terms reference level, anchor level, gain structure, dB, dBU, crest factor, etc. all form an ill defined blur. My interest is in protecting one of my five senses. No amount of money and equipment swapping will ever reclaim lost hearing! Now with oodles of distortion free headroom I need to be careful.

Specifically -
JBL 4367 - 94 dB, 300W
Benchmark AHB2 in bridged mono 380W
SONY XA5400ES Compact Disc Player

What I find is -24 dB set on the preamp (with 0 dB being no voltage gain or cut with respect to the source signal) is too loud on most recordings - especially Pop and Jazz. On the 1964 SONY Classical recording of Petrushka, Ormandy (SBK 47664) a gain of -24 dB is pretty realistic as it is on many other classical recordings.
Some recordings sound loud no matter what the volume. Take Jimmy Smith with Kenny Burrell (Phono 870267) for example (listening to him now @ -34 dB)
Much of my listening is far-field, though the speakers are only about 6' apart in an open floor plan of about 1200 sq. feet.

The inverse square law relating to how loudness decreases with distance from the source - how is it affected by a stereo pair? Get on axis near-field with the speakers and just try and keep your mouth shut. Awesome!

So I have a new definition of LOUD and I want to be careful and have some consistency.
I feel -24 dB is a good reference level and am wondering how that relates live sound and the recording process.




mikewerner
mikewerner OP
119 posts
 

UPDATE:

 

It is time for a correction. After playing around for a while with the low power amps I have come to the conclusion that they do not sound "more like music at all volumes." Instead each puts its own spin on the sound and gets to sound less like music at higher volumes.

 

Switching back to the Harmon duo, specifically the ML 534 paired with the JBL4367, noticeable are the MACRO dynamics and KICK. Back is the house filling sound!

 

So, if you don't feel too silly sitting near-field to these speakers the lower powered amps are fun... Unfortunately though, the first glorious watt (or 40 watts) may ultimately not be enough for the 4367.

mikewerner OP
119 posts
 

I forgot to mention,

Also noticeable with the change is the HUGE soundstage. With the right recordings I am immersed in a sound field that extendsr beyond the boundaries of the room. Be it Alan Lomax "Southern Journey" or Barbie "The Album" the effect is of being surrounded by sound.

mikewerner OP
119 posts
 

UPDATE:

I’ve finally established a reference level for playback in my listening room. It took yet another new amp with an interesting property. A friend recently commented, "It sounds the same when you turn it down." Think about that. Opposed to the low power amps which sound better when you turn them down, and the high power amps which sound better when you turn them up, you get the same quality of sound at all levels. This obviously makes it easier.

The other thing is I prefer the 2 Ohm tap and I’ll tell you why in a minute.

Have you guessed it yet? (I’m the slime oozing out of your TV set) - sorry.

It’s a MC462.

I have been listening to the new amp for the past 2 months and on one recording the difference between the 2 and 4 Ohm taps is readily apparent; on the 4 Ohm tap the classical guitar sounds compressed and the violin sounds way too good to be true. (Hadelich/Villegas "Histoire du Tango").

Using the 2 Ohm tap, the amp is the most honest I have heard. I could speculate why, but why bother? (Do note that I mentioned the VARIAC earlier in the thread.) And no, I am not using the VARIAC with this amp.

An added bonus is that it warms up and is ready to play in the time it takes to brush your teeth.

I love it!

 

 

toddalin's avatar
toddalin
216 posts
 

The EPDR does drop to 2.4 ohms between 885 and 950 Hz and 2.5 ohms between 70 and 80 Hz, so...

https://www.stereophile.com/content/jbl-4367-studio-monitor-loudspeaker-measurements

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